1. Field of the Invention
The present invention relates to digital televisions (TVs), and more particularly, to a video processing apparatus and a method thereof.
2. Description of the Prior Art
Within a digital television (TV), a controller chip typically utilizes a blending module to blend video data from different sources, e.g., video frames transmitted from content/service providers, logo information, scrolling banner information, caption information, and/or on-screen display (OSD) information generated by the digital TV. The blended data is then transmitted to a display panel for further display. Real time calculation and display for the video data from these different sources mentioned above require a portion of bus bandwidth of the digital TV.
An example of typically encoded information transmitted from the content/service provider is subtitle data, including logo information, scrolling banner information, and/or caption information. The subtitle data is decoded by a subtitle decoder and converted into corresponding image data. After certain processing operations such as scaling and/or filtering, the image data is then blended with the other video data mentioned above, e.g. the video frames and the OSD information. The amount of the image data generated in the scaling and filtering processing is considerably large. As a result, the bus bandwidth of the digital TV is heavily occupied, and therefore the overall display performance of the digital TV becomes significantly hindered.